Word Warp is another of my favorite iPhone word games. (I currently just have the free version, which shows ads between rounds.) It is a simple word scramble where you attempt to form all the words you can from a set of 6 letters.
In each round you are presented with a sequence of letter tiles. You tap them to form words. If you can find the word that uses all 6 tiles, you advance to the next round. If not, Game Over. Your score for each round is based on the number of words you create.
If you are just not seeing the word, you can hit the WARP button to resequence the tiles, which may or may not help.
The game is simple but addictive. Some of the sounds are a bit annoying, so you might prefer playing it with the sound turned off.